Belted absorbent article

ABSTRACT

A belted absorbent article includes an absorbent structure extending about a first longitudinal axis, the absorbent structure including a topsheet, a backsheet and an absorbent batt disposed between the topsheet and the backsheet, the absorbent structure having a transverse axis dividing the absorbent structure into a front panel terminating in a front end region and a rear panel terminating in a rear end region, the absorbent structure being delimited by opposed longitudinal edges and opposed transverse edges, and a pair of opposed belt halves including nonwoven material attached to the absorbent structure at the rear end region of the rear panel, each of the belt halves being attached by a respective joint, each belt half extending about a longitudinal axis of the belt such that each belt half extends outwardly from a respective longitudinal edge of the absorbent structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. Ser. No. 10/684,585,filed on Oct. 15, 2003, which is a continuation of U.S. Ser. No.09/902,656, filed on Jul. 12, 2001, which issued as U.S. Pat. No.6,726,670, on Apr. 27, 2004, and which claims the priority of SwedishPatent Application No. SE 0002660-9, filed in Sweden on Jul. 13, 2000,and claims the benefit of U.S. Provisional Application No. 60/218,050,filed in the United States on Jul. 13, 2000. The contents of SwedishPatent Application No. SE 0002660-9 and U.S. Provisional Application No.60/218,050 are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a belted absorbent article in the formof a diaper, an adult incontinence garment, and the like, comprising anabsorbent structure and a pair of opposed belt halves attached to theabsorbent structure at an end region thereof.

2. Discussion of Related Art

Conventional diapers for young children generally comprise an absorbentstructure made up of an absorbent core sandwiched between a liquidpervious topsheet and a liquid-impervious backsheet. The absorbentstructure has a front panel generally covering the child's abdomen whenworn and a rear panel generally covering the child's buttocks. The frontand rear panels terminate in front and rear end regions respectively. Inorder to secure the diaper about the child, the front and rear endregions are provided with cooperating fastening means, for example inthe form of a hook-and-loop fastening system or, alternatively, anadhesive tape tab system on the rear end region cooperating with alanding zone on the front end region. To fit the diaper to the child,the child is normally laid down on his/her back, the diaper is insertedunder the child such that the rear panel covers the child's buttocks,the front panel is drawn between the child's legs to cover the abdomenand the fastening system is employed to join the longitudinal sides ofthe respective front and rear end regions together.

Since it is almost exclusively a guardian who changes a child's diaper,the above-described method of securing a diaper to a child is generallyfully satisfactory. However, particularly for incontinent adults who arecapable of changing their own diapers, such a method of securing anabsorbent article about the body is inconvenient, primarily because theact of securing the absorbent article about the adult body is conductedwhen standing. Thus, it is awkward for the wearer to simultaneously holdthe absorbent article to the body in its correct orientation whilstfastening the front and rear end regions to each other.

To at least partially alleviate the above-mentioned inconvenience,belted absorbent articles have been proposed. For example, a beltedabsorbent article is disclosed in FR-A-2 586 558 in which a one-piecebelt is attached to the backsheet of an absorbent structure. The articleis secured about the wearer by bringing the article to the rear of thewearer to thereby cover the buttocks, fastening the belt about the waistof the wearer and then drawing the front end region of the absorbentstructure between the legs of the wearer and attaching the front endregion to fastening means on the belt.

EP-B-0 729 329 discloses a belted absorbent article in which, ratherthan using a single belt attached to the absorbent structure, two belthalves are employed, with each belt half extending from a respectivelongitudinal edge of the absorbent structure. An advantage of thisconstruction over that disclosed in FR-A-2 586 558 is that less beltmaterial is needed. However, because two belt halves are employed, thejoint between each belt half and the absorbent structure must be capableof withstanding the tension forces to which the belt halves aretypically subjected during use.

Particularly in terms of adult incontinence diapers, the size of wearersvaries greatly. In order to rationalize production and storage as muchas possible, it is preferable to have as few product size variations aspossible. This implies, on the other hand, that each product size mustbe capable of fitting wearers of widely diverging shape and size. As aconsequence, the forces to which the belt halves are subjected duringuse will be, at least to a certain extent, dependent on the size of thewearer. To keep manufacturing costs low, it is of course advantageous touse as little material as possible. Nevertheless, a product must besufficiently strong to fulfill its intended purpose.

As is apparent from FIG. 1, when a belted absorbent article 10 issecured to a wearer, an angle α is created between, in effect, thelongitudinal axis L of the belt half and the transverse axis T of theabsorbent structure (it being assumed in the illustrated embodiment thatthe longitudinal edge of the belt half is parallel to the longitudinalaxis of the belt half). Depending on the size of the wearer in relationto the size of the article, the value of a will vary. The greater thesize of wearer, the greater the value of a will be. As the angle αincreases, an increasing shear force is applied to the joint between thebelt half and the absorbent structure.

The present applicant has discovered that, in order for a beltedabsorbent article to function satisfactorily, while still keepingmanufacturing costs as low as reasonably possible, the joint betweeneach belt half and the absorbent structure should preferably meetcertain minimum requirements depending on the angle α.

OBJECTS AND SUMMARY

It is therefore an object of the present invention to provide a beltedabsorbent article which functions satisfactorily while still keepingmanufacturing costs as low as reasonably possible.

This object is achieved by means of the belted absorbent articlecomprising an absorbent structure extending about a first longitudinalaxis, the absorbent structure including a topsheet, a backsheet and anabsorbent batt disposed between the topsheet and the backsheet, theabsorbent structure having a transverse axis dividing the absorbentstructure into a front panel terminating in a front end region and arear panel terminating in a rear end region, the absorbent structurebeing delimited by opposed longitudinal edges and opposed transverseedges, and a pair of opposed belt halves attached to the absorbentstructure at the rear end region of the rear panel by a respectivejoint, each belt half extending about a second longitudinal axis suchthat each belt half extends outwardly from a respective longitudinaledge of the absorbent structure. The joint between each belt half andthe absorbent structure is designed such that when each belt half issubjected to a tension force of 35 N acting along the secondlongitudinal axis and the second longitudinal axis creates an angle α tosaid transverse axis of said absorbent structure, the following minimumaverage release times (t) of each said belt half from said absorbentstructure are attained:

when α=10°, t≧720 seconds;

when α=20°, t≧330 seconds;

when α=25°, t≧240 seconds;

when α=30°, t≧180 seconds; and

when α=40°, t≧75 seconds.

In a preferred embodiment of the invention, the following minimumaverage release times (t) of each belt half from the absorbent structureare attained:

when α=10°, t≧740 seconds;

when α=20°, t≧340 seconds;

when α=25°, t≧245 seconds;

when α=30°, t≧190 seconds; and

when α=40°, t≧80 seconds.

In a more preferred embodiment of the invention, the following minimumaverage release times (t) of each belt half from the absorbent structureare attained:

when α=10°, t≧760 seconds;

when α=20°, t≧350 seconds;

when α=25°, t≧250 seconds;

when α=30°, t≧200 seconds; and

when α=40°, t≧85 seconds.

In a further embodiment of the invention, the following minimum averagerelease times (t) of each belt half from the absorbent structure areattained:

when α=10°, t≧780 seconds;

when α=20°, t≧360 seconds;

when α=25°, t≧255 seconds;

when α=30°, t≧210 seconds; and

when α=40°, t≧90 seconds.

In accordance with a most preferred embodiment of the invention, thefollowing minimum average release times (t) of each belt half from theabsorbent structure are attained:

when α=10°, t≧800 seconds;

when α=20°, t≧370 seconds;

when α=25°, t≧260 seconds;

when α=30°, t≧220 seconds; and

when α=40°, t≧00 seconds.

Thus, in accordance with the invention, by ensuring that the jointbetween each belt half and the absorbent structure can withstand a forceof 35 N at predetermined values of the angle α for a minimum averagerelease time per chosen angle, it has been found in practice thatfailure of the belted absorbent article due to loosening of the belthalves does not occur, at least not during normal use.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in the following in greater detail byway of example only and with reference to the attached drawings, inwhich:

FIG. 1 is a schematic side view of a belted absorbent article secured toa wearer;

FIG. 2 is a schematic plan view of a belted absorbent article accordingto the present invention;

FIG. 3 is an enlarged view of the joint between a belt half and theabsorbent structure of the belted absorbent article according to thepresent invention;

FIG. 4 is a schematic view of a cut out section of the article accordingto the present invention being subjected to a test procedure;

FIG. 5 is a schematic plan view illustrating sections of the beltedabsorbent article according to the present invention which are to be cutout and tested;

FIG. 6 is a schematic elevational view of a test rig for subjecting cutout sections of the belted absorbent product to a test procedure;

FIG. 7 is an engineering drawing in the form of an elevational view ofone component of the test rig of FIG. 6;

FIG. 8 is an engineering drawing in the form of an end view of thecomponent of FIG. 7;

FIG. 9 is an enlarged view of a portion of the component of FIG. 8;

FIG. 10 is an engineering drawing in the form of an elevational view ofa second component of the test rig of FIG. 6;

FIG. 11 is an engineering drawing in the form of an end view of thecomponent of FIG. 10;

FIG. 12 is an enlarged view of a portion of the component of FIG. 11;

FIG. 13 is an engineering drawing in the form of an elevational view ofa third component of the test rig of FIG. 6; and

FIG. 14 is an engineering drawing in the form of an end view of thecomponent of FIG. 13.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In the drawings, reference numeral 10 generally denotes a beltedabsorbent article according to the present invention. The expression“belted” implies that the article is provided with means which passaround at least a portion of the waist of a wearer when worn and whichmeans meet to thereby secure the article around the waist of the wearer.In the present invention, these means are belt halves 12, 14.Preferably, the invention is to be practiced on a disposable article. Inthis respect, the term “disposable” means any article which is notintended to be laundered and which is normally discarded once removedfrom the wearer.

In addition to the belt halves 12, 14, the belted absorbent articlefurther comprises an absorbent structure 16 extending about a firstlongitudinal axis 18. Thus, when the article is being worn, the firstlongitudinal axis will generally bisect the wearer into a left hand sideand a right hand side when viewed from above. The absorbent structure 16includes a topsheet 20, a backsheet 22 and an absorbent batt 24 disposedbetween the topsheet and the backsheet. The specific components used toform the absorbent structure may be any of the types commonly used forsuch purposes. For example, a suitable topsheet 20 may be any softflexible non-irritating liquid permeable material, such as woven ornonwoven webs of natural fibers (e.g. wood or cotton fibers), syntheticfibers (e.g. polyester or polypropylene fibers or coform fibers),combinations of natural and synthetic fibers, apertured films or porousfoams. Preferably, the topsheet 20 is manufactured from a nonwovenspunbonded polypropylene material having a basis weight of less than 20g/m². Nevertheless, when the topsheet comprises a nonwoven web, thenonwoven web may instead be carded, wet-laid, meltblown, hydroformed orhydroentangled. The backsheet 22 is impervious to liquids and ispreferably manufactured from a thin plastic film such as polyethylene,polypropylene, polyvinyl-chloride, or the like, or composite materialssuch as a film coated nonwoven material. The absorbent core 24 may bemade in widely varying sizes and shapes and may comprise any suitablewettable hydrophilic fibers such as cellulosic fibers, possibly blendedwith synthetic polyolefin fibers. In certain embodiments, the absorbentcore 24 may comprise a mixture of superabsorbent hydrogel-formingparticles mixed with the hydrophilic fibers.

The topsheet 20 and the backsheet 22 are connected together, eitherdirectly or indirectly, using any suitable known means. For example, thetopsheet and the backsheet can be affixed directly to each other inselected areas using continuous or patterned layers of adhesive. Theadhesive layer or layers may be sprayed or extruded in lines or dots.

As is most clearly apparent from FIG. 2, the absorbent structure has atransverse axis T dividing the structure into a front panel 26terminating in a front end region 28 and a rear panel 30 terminating ina rear end region 32. The absorbent structure is delimited by opposedlongitudinal edges 34 and opposed transverse edges 36. Projecting fromits opposed longitudinal edges 34, the front end region 28 displaysfastening tabs 38. In a manner which will be explained in greater detailbelow, the fastening tabs 38 form part of a fastening system and arearranged to cooperate with corresponding parts of the fastening systemon the belt halves 12, 14. Although the fastening tabs 38 are shownprojecting from the longitudinal edges 34 of the front panel of theabsorbent structure 16, it is to be understood that the tabs may insteadproject from the transverse edge 36. In a further alternativeembodiment, the fastening tabs 38 may be in the form of one or morepatches affixed to the topsheet 20 on the front panel 26.

Each belt half extends about a respective longitudinal axis (hereinafterreferred to as the second longitudinal axis) 40, 42, with the belthalves being joined to the absorbent structure 16 such that the two belthalves 12, 14 extend generally perpendicularly with respect to the firstlongitudinal axis 18 of the absorbent structure 16. Accordingly, in theshown embodiment, the two belt halves 12, 14 extend generallyperpendicularly from the longitudinal edges 34 at the rear end region 32of the rear panel 30 of the absorbent structure 16. It is, however, tobe understood that the belt halves may be manufactured such that theyform an angle to either the first longitudinal axis 18 or to thelongitudinal edges 34. The belt halves may be made of any suitablematerial or material combinations. In an exemplary embodiment, the belthalves are made from a laminate of an embossed transparent polypropylenefilm and a thermobonded nonwoven web of 30 g/m² basis weight. Forimproved wearer comfort, the belt halves are attached to the absorbentstructure such that, when worn, the nonwoven web faces the wearer. Inanother embodiment, the belt halves may be made exclusively of nonwovenmaterial. Depending on the intended size of the wearer, each belt half12, 14 has a transverse extension of typically 10 to 12 cm and alongitudinal extension (i.e. the extension beyond the longitudinal edge34 of the absorbent structure) of, for example, 35 cm. The belt halvesare preferably identical, though it is to be understood that theabsorbent article of the present invention may also have belt halves ordifferent length and/or width.

The inside surface, i.e. that surface of the belt half facing the wearerwhen worn, of one belt half (belt half 14 in FIG. 2) is provided with afirst fastening means 44 for releasable engagement with a complementarysecond fastening means 46 on the outer surface of the other belt half 12to thereby allow the belt to be secured around the waist of the wearer.The actual type of belt fastening means may be any of those known in theart, for example a hook-and loop system, an adhesive system, a system ofbuttons and button-holes, etc. Irrespective of the type of fasteningsystem employed, the fastening system should be capable of allowingadjustment of the tension of the belt halves around the waist of thewearer. Thus, in the embodiment shown on FIG. 2, the first fasteningmeans is a patch of hook material while the second fastening means is astrip of loop material extending over a significant length of the belthalf 12. It will of course be apparent to the skilled person that morethan one patch of hook material may be used and that the strip of loopmaterial may be a plurality of smaller patches of loop material.

The surface of the belt halves remote from the wearer when worn, i.e.,the outer surface of the belt halves, is provided with means (not shown)forming a part of the fastening system of the absorbent article. Themeans on the belt halves is complementary to, and therefore dependenton, the type of fastening tab 38 employed in the front end region 28 ofthe front panel 26. Thus, if the fastening tabs 38 are adhesive tabs, atleast a region of the outer surface of the belt halves 12, 14 should becapable of releasable engagement of the adhesive tabs. In the case inwhich the outer surface of the belt halves is a plastics film, it isadvantageous to provide a reinforced so-called landing zone or zones forthe tabs to engage with. If the fastening tabs 38 are hook tabs of ahook-and-loop fastening system, the outer surface of the belt halveswill be provided with, or made from, a loop material for engagement withthe hook fastening tabs. Another possibility is that the outer surfaceof the belt halves is provided with patches of hook material forengagement with loop material of the topsheet 20 or patches of loopmaterial attached to the topsheet in the front end region 28 of thefront panel 26.

In a manner known per se in the art, the absorbent article of thepresent invention may be provided with elasticated leg cuffs to therebyprovide improved sealing of the article around the legs of the wearerwhen worn. As is most clearly shown in FIGS. 2 and 3, the absorbentstructure 16 is provided with elastic ribbons 48 or strands affixedbetween the topsheet 20 and the backsheet 22. The elastic ribbons extendfrom an area in the rear end region 32 remote from the transverse edge36 along a path generally parallel to the longitudinal edges 34 of theabsorbent structure to an area in the front end region 28 remote fromits transverse edge 36. In the illustrated embodiment, three elasticribbons 48 or strands are shown for each leg cuff. The person skilled inthe art will, however, appreciate that the actual number of elasticribbons may be varied, as may their size. Thus, although the ribbons areillustrated as threads, it will be appreciated that strips of elasticmaterial may be used instead.

Each belt half 12, 14 is attached to the absorbent structure 16 at therear end region 32 of the rear panel 30 by a respective joint, generallydenoted by reference numeral 50. One example of a joint 50 which may beused in the absorbent article of the present invention is illustrated inFIG. 3. It is to be understood that, although the joint will bedescribed below only with reference to one belt half 14, an identicaljoint may be used for the other belt half 12. A length 52 of the belthalf 14 is attached to the absorbent structure 16 at the rear end region32 between the topsheet 20 and the backsheet 22. The length 52 of thebelt half thus sandwiched between the topsheet and backsheet will varydepending on the size of the absorbent article, but is typically between8 and 10 cm. When, and in what order, the belt half is attached to thetopsheet and backsheet will depend on the chosen manufacturing process.The belt half 14 is generally spaced a short distance, for example about1 cm, from the transverse edge 36 of the absorbent structure and, priorto being worn, the longitudinal axis 42 of the belt half may extendsubstantially parallel to the transverse edge. Thus, in the illustratedembodiment, the longitudinal axis of the belt half extends parallel tothe transverse axis T of the absorbent structure. The joint 50 betweenthe belt half 14 and the rear end region 32 comprises two spacedsubstantially parallel lines of attachment 54 between the belt half andthe backsheet 22. The line of attachment 54 adjacent the longitudinaledge 34 of the absorbent structure 16 may be spaced a short distancefrom the longitudinal edge. This line of attachment is generallynarrower than the line of attachment remote from the longitudinal edge34 of the absorbent structure. The two spaced lines of attachment 54generally extend from the transverse edge 36 of the rear end regionparallel to the longitudinal axis 18 of the absorbent structure acrossthe entire width of the belt half and slightly beyond. Although thelines are shown to be continuous, it is to be understood that they mayinstead comprise intermittent lines of attachment. Preferably, the linesof attachment 54 are adhesive bond lines, though any attachment methods,such as thermal or ultrasonic bonding, may be employed.

The two spaced substantially parallel lines of attachment 54 at leastpartially delimit a non-attached longitudinally extending region 56between the belt half 14 and the backsheet 22. This non-attached region56 permits the elastic ribbons 48 or strands of the elasticized legcuffs to snap back during manufacture. Thus, free ends of the elasticribbons 48 or strands reside in the non-attached longitudinallyextending region 56. To firmly anchor the elastic ribbons 48 within theabsorbent structure 16, the joint 50 between the belt half 14 and therear end region 32 further comprises a region 58 of attachment betweenthe backsheet 22 and the belt half. The region 58 of attachment extendsbetween the two spaced substantially parallel lines of attachment 54over the elastic ribbons 48. Advantageously, the region 58 of attachmentextends in the longitudinal direction beyond the point at which the twospaced parallel lines of attachment 54 terminate. The joint 50 betweenthe belt half 14 and the rear end region 32 may further comprise atleast one region of bonding between the belt half and the topsheet 20.Such region may comprise substantially the entire surface of the belthalf which lies adjacent the topsheet 20. This region of bonding may besuitably achieved by spray bonding the topsheet to the belt half.

In accordance with the present invention, the joint 50 is designed tomeet certain minimum requirements. The present inventors have discoveredthat, for the absorbent article to function satisfactorily, the joint 50should be capable of withstanding a certain tension force applied to thebelt halves at a certain angle α to the transverse axis of the absorbentstructure for a certain minimum period of time. Thus, and in a mannerwhich will be explained in greater detail below, the joint is subjectedto a test procedure such that, and as illustrated in FIG. 4, a portionof the absorbent structure 16 is secured to a test rig, generallydenoted reference numeral 60, and a load of 35 N is applied to the belthalf 14 while the belt half external of the absorbent structure 16 ismaintained at a predetermined angle α to the transverse axis of theabsorbent structure. The time up to failure of the joint, i.e. when thebelt half completely dissociates from the absorbent structure, ismeasured. The time to failure is hereinafter referred to as the releasetime of the joint. In accordance with the present invention, the minimumaverage release times of the joint should be:

when α=10°, t≧720 seconds;

when α=20°, t≧330 seconds;

when α=25°, t≧240 seconds;

when α=30°, t≧180 seconds; and

when α=40°, t≧75 seconds.

In a preferred embodiment of the invention, the following minimumaverage release times (t) of each belt half from the absorbent structureare attained:

when α=10°, t≧740 seconds;

when α=20°, t≧340 seconds;

when α=25°, t≧245 seconds;

when α=30°, t≧190 seconds; and

when α=40°, t≧80 seconds.

In a more preferred embodiment of the invention, the following minimumaverage release times (t) of each belt half from the absorbent structureare attained:

when α=10°, t≧760 seconds;

when α=20°, t≧350 seconds;

when α=25°, t≧250 seconds;

when α=30°, t≧200 seconds; and

when α=40°, t≧85 seconds.

In a further embodiment of the invention, the following minimum averagerelease times (t) of each belt half from the absorbent structure areattained:

when α=10°, t≧780 seconds;

when α=20°, t≧360 seconds;

when α=25°, t≧255 seconds;

when α=30°, t≧210 seconds; and

when α=40°, t≧90 seconds.

In accordance with a most preferred embodiment of the invention, thefollowing minimum average release times (t) of each belt half from theabsorbent structure are attained:

when α=10°, t≧800 seconds;

when α=20°, t≧370 seconds;

when α=25°, t≧260 seconds;

when α=30°, t≧220 seconds; and

when α=40°, t≧00 seconds.

The minimum average release times are established in the followingmanner.

With reference to FIG. 5, a section of the rear panel 30 including thejoint 50 is cut out from the absorbent structure 16. A first cut line 62is made parallel to the longitudinal axis 18 of the absorbent article atleast 45 mm from the end edge of the belt half 14 nearest thelongitudinal axis 18. The first cut line 62 extends beyond the loweredge, i.e. the edge nearest the transverse axis T of the absorbentarticle, of the belt half 14 by at least 45 mm. The first cut lineintersects a second cut line 64 extending parallel to the transverseaxis T of the absorbent article at least 45 mm from the lower edge ofthe belt half 14. The thus cut out section of the absorbent structure 16including the joint 50 is then clamped in the test rig 60 which will bedescribed in greater detail in the following.

With reference to FIG. 6, the test rig 60 comprises a rectangular baseplate 66 to which a rotatable plate 68 is mounted. A pair of clamps 70spaced at 90° to each other is mounted on the rotatable plate 68. Withreference to FIG. 4, the rotatable plate 68 can be rotated with respectto the rectangular base plate 66 such that suitable values of the angleα are obtainable. The test rig 60 is provided with locking means toenable the rotatable plate to be locked at angular positions at whichdesired values of a are obtained. The rectangular base plate 66 may beprovided with holes 72 to enable the base plate to be maintained in avertical position on a frame (not shown) or the like.

Dimensions and constructional details of the test rig 60 will beapparent from the attached FIGS. 7 to 14.

The method for establishing the minimum average release times is thefollowing.

Sections are cut out from fifty identical absorbent articles. In orderto avoid the influence of aging of the articles on the test results, thearticles should be no more than 6 months old, i.e., the test is to beperformed on articles which have been manufactured during the past sixmonths. The cut out section of a first absorbent structure 16 is securedby the clamps 70 to the test rig 60, as shown in FIG. 4. The orientationof the cut out section must be such that the clamps 70 clamp the cut outsection along lines parallel to the transverse axis T and thelongitudinal axis 18 of the absorbent article. In FIG. 4, the edges ofthe belt half 14 within the absorbent structure 16 are parallel to thetransverse and longitudinal axes respectively. Thus, these edges areparallel to, and spaced from the clamps 70. In order to ensure that theclamps do not contact the belt half 14, a spacing of about 1 cm may beemployed. The rectangular base plate 66 is held vertically and therotatable plate 68 is rotated until an angle α of 10° is attained. Therotatable plate is locked at this position and a weight is clamped tothe free end of the belt half 14. The weight is slowly released until itapplies a tension to the belt half. The weight is then allowed to hangfreely. The weight and clamp together apply a force of 35 N to the belthalf. As soon as the weight is allowed to hang freely, a stop watch isstarted. As soon as the belt half completely dissociates from theabsorbent structure, i.e., when the weight hits the floor, the stopwatch is stopped and the elapsed time is noted.

The above procedure is repeated for nine further cut out sections atα=10°.

For the next ten cut out sections, the above procedure is repeated forα=20°.

Batches of ten cut out sections are then subjected to the aboveprocedure, but for α=25°, 30° and 40°.

EXAMPLE

The above procedure was conducted on a belted absorbent article toensure that its joint 50 between each belt half and the absorbentstructure is sufficiently strong. The following results were obtained(note that the elapsed time is given in minutes and seconds):

α = 10° 20° 25° 30° 40° Sample 1 12:31 05:35 03:21 04:23 01:49 2 10:1605:42 05:51 04:14 01:52 3 12:52 06:27 04:41 03:25 01:25 4 13:34 07:1003:37 02:58 01:17 5 11:05 05:43 04:28 02:59 01:45 6 11:45 05:21 04:0103:29 00:52 7 16:24 07:11 03:59 02:18 01:25 8 12:07 05:00 04:39 02:3901:09 9 11:27 04:57 03:27 03:36 00:46 10 11:34 04:15 03:28 03:36 01:19Average: 12:21 05:44 04:09 03:21 01:21 St. dev. .01:41  00:57 00:4600:39 00:22 Min 10:16 04:15 03:21 02:18 00:46 Max 16:24 07:11 05:5104:23 01:52

Thus, the average release times for the joint of the EXAMPLE are:

when α=10°, t=741 seconds;

when α=20°, t=344 seconds;

when α=25°, t=249 seconds;

when α=30°, t=201 seconds; and

when α=40°, t=81 seconds.

The above EXAMPLE relates to a belted absorbent article in which thebelt halves are substantially rectilinear, i.e., the upper and lowerlongitudinal edges of the belt halves are substantially parallel to thesecond longitudinal axis 42. Thus, the angle α may be determined eitherby measuring the angle as shown in FIG. 4, or by measuring the anglesubtended by the second longitudinal axis 42. In cases in which the belthalves are non-rectilinear, i.e., the belt halves are curved, the angleα is determined by hanging the load of 35 N from the remote end of thebelt half such that the load acts along the longitudinal axis of thebelt half and determining the mid-point of the belt half between itsupper and lower longitudinal edges at the joint 50. A vertical line willthus be attained between the midpoint and the load. The angle that thisvertical line subtends to the transverse axis T of the absorbent articlecorresponds to the angle α.

The invention is not restricted to the embodiments described above andshown in the drawings, but may be varied within the scope of theappended claims. For example, the topsheet 20 of the absorbent structure16 may be provided with so-called standing gathers to assist inretaining bodily wastes within the confines of the absorbent structure.

1. A belted absorbent article comprising: an absorbent structureextending about a first longitudinal axis, said absorbent structureincluding a topsheet, a backsheet and an absorbent batt disposed betweensaid topsheet and said backsheet, said absorbent structure having atransverse axis dividing the absorbent structure into a front panelterminating in a front end region and a rear panel terminating in a rearend region, said absorbent structure being delimited by opposedlongitudinal edges and opposed transverse edges, and a pair of opposedbelt halves comprising nonwoven material attached to said absorbentstructure at said rear end region of said rear panel, each of said belthalves being attached by a respective joint, each belt half extendingabout a longitudinal axis of the belt such that each belt half extendsoutwardly from a respective longitudinal edge of the absorbentstructure, wherein each of said joints between each said belt half andsaid absorbent structure is such that when each said belt half issubjected to a tension force of 35 N acting along said longitudinal axisof the belt, and said longitudinal axis of the belt creates an angle (α)to said transverse axis of said absorbent structure, the followingminimum average release times (t) of each said belt half from saidabsorbent structure are attained: when α=10°, t≧720 seconds; when α=20°,t≧330 seconds; when α=25°, t≧240 seconds; when α=30°, t≧180 seconds; andwhen α=40°, t≧75 seconds.
 2. The article as claimed in claim 1, whereinthe following minimum average release times (t) of each said belt halffrom said absorbent structure are attained: when α=10°, t≧740 seconds;when α=20°, t≧340 seconds; when α=25°, t≧245 seconds; when α=30°, t≧190seconds; and when α=40°, t≧80 seconds.
 3. The article as claimed inclaim 1, wherein the following minimum average release times (t) of eachsaid belt half from said absorbent structure are attained: when α=10°,t≧760 seconds; when α=20°, t≧350 seconds; when α=25°, t≧250 seconds;when α=30°, t≧200 seconds; and when α=40°, t≧85 seconds.
 4. The articleas claimed in claim 1, wherein the following minimum average releasetimes (t) of each said belt half from said absorbent structure areattained: when α=10°, t≧780 seconds; when α=20°, t≧360 seconds; whenα=25°, t≧255 seconds; when α=30°, t≧210 seconds; and when α=40°, t≧90seconds.
 5. The article as claimed in claim 1, wherein the followingminimum average release times (t) of each said belt half from saidabsorbent structure are attained: when α=10°, t≧800 seconds; when α=20°,t≧370 seconds; when α=25°, t≧260 seconds; when α=30°, t≧220 seconds; andwhen α=40°, t≧100 seconds.
 6. The article as claimed in claim 1, whereineach said belt half is attached to said absorbent structure at said rearend region between said topsheet and said backsheet.
 7. The article asclaimed in claim 6, wherein each of said joints between each said belthalf and said rear end region comprises two spaced substantiallyparallel lines of attachment between each said belt half and saidbacksheet.
 8. The article as claimed in claim 7, wherein said two spacedsubstantially parallel lines of attachment are adhesive bond lines. 9.The article as claimed in claim 1, wherein each of said belt halvescomprises a film/nonwoven laminate.
 10. The article as claimed in claim1, wherein each of said belt halves consists of nonwoven material. 11.The article as claimed in claim 1, wherein the topsheet comprisesnonwoven material.
 12. The article as claimed in claim 1, wherein thebacksheet comprises a film/nonwoven laminate.
 13. The article as claimedin claim 1, wherein each of said belt halves consists of nonwovenmaterial, wherein the topsheet comprises nonwoven material, and whereinthe backsheet comprises a film/nonwoven laminate.
 14. The article asclaimed in claim 1, wherein each of said belt halves is attached to saidabsorbent structure with adhesive.
 15. The article as claimed in claim1, wherein each of said belt halves is attached to said absorbentstructure with a thermal or ultrasonic bond.
 16. A belted absorbentarticle comprising: an absorbent structure extending about a firstlongitudinal axis, said absorbent structure including a topsheet, abacksheet and an absorbent batt disposed between said topsheet and saidbacksheet, said absorbent structure having a transverse axis dividingthe absorbent structure into a front panel terminating in a front endregion and a rear panel terminating in a rear end region, said absorbentstructure being delimited by opposed longitudinal edges and opposedtransverse edges, and a pair of opposed belt halves comprisingexclusively nonwoven material attached to said absorbent structure atsaid rear end region of said rear panel and at least one fastening tab,each of said belt halves being attached by a respective joint, each belthalf extending about a longitudinal axis of the belt such that each belthalf extends outwardly from a respective longitudinal edge of theabsorbent structure, wherein each of said joints between each said belthalf and said absorbent structure is such that when each said belt halfis subjected to a tension force of 35 N acting along said longitudinalaxis of the belt and said longitudinal axis of the belt creates an angle(α) to said transverse axis of said absorbent structure, the followingminimum average release times (t) of each said belt half from saidabsorbent structure are attained: when α=10°, t≧720 seconds; when α=20°,t≧330 seconds; when α=25°, t≧240 seconds; when α=30°, t≧180 seconds; andwhen α=40°, t≧75 seconds.
 17. A belted absorbent article comprising: anabsorbent structure extending about a first longitudinal axis, saidabsorbent structure including a topsheet, a backsheet and an absorbentbatt disposed between said topsheet and said backsheet, said absorbentstructure having a transverse axis dividing the absorbent structure intoa front panel terminating in a front end region and a rear panelterminating in a rear end region, said absorbent structure beingdelimited by opposed longitudinal edges and opposed transverse edges,and a pair of opposed belt halves comprising exclusively nonwovenmaterial attached to said absorbent structure at said rear end region ofsaid rear panel and at least one fastening tab, each of said belt halvesbeing attached by a respective joint, each belt half extending about alongitudinal axis of the belt such that each belt half extends outwardlyfrom a respective longitudinal edge of the absorbent structure, whereineach of said joints between each said belt half and said absorbentstructure comprises means for joining whereby when each said belt halfis subjected to a tension force of 35 N acting along said longitudinalaxis of the belt and said longitudinal axis of the belt creates an angle(α) to said transverse axis of said absorbent structure, the followingminimum average release times (t) of each said belt half from saidabsorbent structure are attained: when α=10°, t≧800 seconds; when α=20°,t≧370 seconds; when α=25°, t≧260 seconds; when α=30°, t≧220 seconds; andwhen α=40°, t≧100 seconds.
 18. A belted absorbent article comprising: anabsorbent structure extending about a first longitudinal axis, saidabsorbent structure including a topsheet, a backsheet and an absorbentbatt disposed between said topsheet and said backsheet, said absorbentstructure having a transverse axis dividing the absorbent structure intoa front panel terminating in a front end region and a rear panelterminating in a rear end region, said absorbent structure beingdelimited by opposed longitudinal edges and opposed transverse edges,and a pair of opposed belt halves comprising nonwoven material attachedto said absorbent structure at said rear end region of said rear panel,each of said belt halves being attached by a respective joint, each belthalf extending about a longitudinal axis of the belt such that each belthalf extends outwardly from a respective longitudinal edge of theabsorbent structure, wherein each of said joints between each said belthalf and said absorbent structure comprises means for joining such thatwhen each said belt half is subjected to a tension force of 35 N actingalong said longitudinal axis of the belt, said longitudinal axis of thebelt creates an angle (α) to said transverse axis of said absorbentstructure, and the following minimum average release times (t) of eachsaid belt half from said absorbent structure are attained: when α=10°,t≧720 seconds; when α=20°, t≧330 seconds; when α=25°, t≧240 seconds;when α=30°, t≧180 seconds; and when α=40°, t≧75 seconds.
 19. A beltedabsorbent article comprising: an absorbent structure extending about afirst longitudinal axis, said absorbent structure including a topsheet,a backsheet and an absorbent batt disposed between said topsheet andsaid backsheet, said absorbent structure having a transverse axisdividing the absorbent structure into a front panel terminating in afront end region and a rear panel terminating in a rear end region, saidabsorbent structure being delimited by opposed longitudinal edges andopposed transverse edges, and a pair of opposed belt halves comprisingnonwoven material attached to said absorbent structure at said rear endregion of said rear panel, each of said belt halves being attached by arespective joint, each belt half extending about a longitudinal axis ofthe belt such that each belt half extends outwardly from a respectivelongitudinal edge of the absorbent structure, wherein each of said belthalves is attached to the absorbent structure between said topsheet andsaid backsheet with the respective joints each comprising at least oneregion of bonding between each said belt half and said topsheet, andeach of said joints is spaced from the longitudinal edge associated withthe respective belt half; wherein each of said joints between each saidbelt half and said absorbent structure is such that when each said belthalf is subjected to a tension force of 35 N acting along saidlongitudinal axis of the belt, and said longitudinal axis of the beltcreates an angle (α) to said transverse axis of said absorbentstructure, the following minimum average release times (t) of each saidbelt half from said absorbent structure are attained: when α=10°, t≧720seconds; when α=20°, t≧330 seconds; when α=25°, t≧240 seconds; whenα=30°, t≧180 seconds; and when α=40°, t≧75 seconds.
 20. The article asclaimed in claim 1, wherein each of said belt halves is attached to theabsorbent structure between said topsheet and said backsheet, and eachof said joints includes a region of attachment between the respectivebelt half and said backsheet and a region of attachment between therespective belt half and said topsheet.
 21. The article as claimed inclaim 20, wherein the region of attachment between the respective belthalf and said backsheet includes first and second spaced substantiallyparallel lines of attachment between each respective belt half and saidbacksheet.
 22. The article as claimed in claim 1, wherein each of saidbelt halves is attached to the absorbent structure between said topsheetand said backsheet, and each of said joints includes at least one of aregion of attachment between the respective belt half and said backsheetand a region of attachment between the respective belt half and saidtopsheet.
 23. The article as claimed in claim 1, wherein each of saidbelt halves is substantially rectangular.